Although two doses of the COVID-19 vaccine provides some protection for people who have received solid organ transplants, they still won¡¯t have enough antibodies to ease up on crucial safety measures such as the use of masks and physical distancing, a study by researchers from Johns Hopkins Medicine has found.
These patients are at a higher risk of developing severe COVID-19 based on their immunosuppressed state and associated comorbidities. And this latest study is a follow up to their previous one, where they found only one in five (17%) participating transplant recipients produced sufficient antibodies after receiving just one jab of a two-dose vaccine regimen.
After receiving two doses of the COVID-19 vaccine, there was a 54 per cent increase in the production of antibodies in the solid organ transplant patients. While it¡¯s high enough to protect patients from a potential SARS-CoV-2 infection, it¡¯s still well below what¡¯s typically seen in people with healthy immune systems.
"Based on our findings, we recommend that transplant recipients and other immunocompromised patients continue to practice strict COVID-19 safety precautions, even after vaccination," lead author Brian Boyarsky said in a statement.
The study, published in the Journal of the American Medical Association (JAMA), advised people who receive solid organ transplants, such as hearts, lungs and kidneys, to take prescribed medication to suppress their immune systems. This will ensure that their body does not reject the received organ.?
Such regimens may interfere with a transplant recipient¡¯s ability to make antibodies to foreign substances, which also includes protective ones generated as a response to vaccines, the researchers said.
For the study, the authors evaluated this immunogenic response for 658 transplant recipients after they received the second dose of either of the two messenger RNA (mRNA) vaccines made by Moderna and Pfizer-BioNTech. None of the test candidates had previously been diagnosed with COVID-19.
Twenty one days after the first jab, only 98 study participants (15%) had developed detectable antibodies against SARS-CoV-2--similar to the 17 per cent reported in March. A month after the second jab, the number of participants with identifiable antibodies increased to 357 out of 658 (54%).
After both vaccine doses were administered, 301 out of 658 participants (46%) had no detectable antibody at all while 259 (39%) only produced antibodies after the second shot.
Additionally, the team also discovered that among the participating patients, the most likely to develop an antibody response were those who were younger, didn¡¯t take immunosuppressive medications (including anti-metabolite drugs), and received the Moderna vaccine.
¡°Given these observations, transplant recipients should not assume that two vaccine doses guarantee sufficient immunity against SARS-CoV-2 any more than it did after just one dose,¡± study co-author Dorry Segev said.